Low Defect FeFe(CN)₆ Framework as Stable Host Material for High Performance Li-Ion Batteries

Low cost and high performance Li-ion batteries have been extensively pursued for grid-scale energy storage applications; however, their development has been impeded for a long time due to the lack of qualified cathode materials with not only decent electrochemical performance but also resource abundance and low price. In this paper, we report Prussian-blue type FeFe(CN)6 nanocrystals with well-controlled lattice defects and perfect nanocubic morphology, which can exhibit a high Li-storage capacity of 160 mAh g(-1), a strong rate performance at 24 C, and a superior cycle stability with 90% capacity retention over 300 cycles. This low defect lattice and its excellent Li-insertion performance might provide a new insight into the design of advanced Li-ion battery materials and also a competitive alternative to the presently developed Li(+) insertion cathodes to develop low cost and high performance Li-ion batteries for grid-scale energy storage applications.